diff --git a/.github/workflows/mypy_primer.yml b/.github/workflows/mypy_primer.yml
index ece6e9f24..72ec3efd0 100644
--- a/.github/workflows/mypy_primer.yml
+++ b/.github/workflows/mypy_primer.yml
@@ -45,12 +45,14 @@ jobs:
             const fs = require('fs').promises;
             try {
               data = await fs.readFile('diff.txt', 'utf-8')
-              await github.issues.createComment({
-                issue_number: context.issue.number,
-                owner: context.repo.owner,
-                repo: context.repo.repo,
-                body: 'Diff from [mypy_primer](https://github.com/hauntsaninja/mypy_primer), showing the effect of this PR on open source code:\n```diff\n' + data + '```'
-              })
+              if (data.trim()) {
+                await github.issues.createComment({
+                  issue_number: context.issue.number,
+                  owner: context.repo.owner,
+                  repo: context.repo.repo,
+                  body: 'Diff from [mypy_primer](https://github.com/hauntsaninja/mypy_primer), showing the effect of this PR on open source code:\n```diff\n' + data + '```'
+                })
+              }
             } catch (error) {
               console.log(error)
             }